= database_cremona_ellcurve =

== Description ==
John Cremona's database of elliptic curves

See https://github.com/JohnCremona/ecdata

This is an optional package, not included by default.

== License ==
Public Domain

== SPKG Maintainers ==
 * R. Andrew Ohana
 * John Cremona

== Dependencies ==
None

=== Patches ===
 * None

== Upstream Contact ==

 * Author: John Cremona
 * Email: john.cremona@gmail.com
 * Website: http://homepages.warwick.ac.uk/staff/J.E.Cremona/

== Update Instructions ==

At the end of either method, copy `SAGE_DATA/cremona/cremona.db` to the src directory of the spkg.

=== Method 1 ===

If the cremona database has already been installed, remove
`SAGE_DATA/cremona/cremona.db`. Run

{{{
sage: sage.databases.cremona.build('cremona','path/to/ecdata.tgz')
}}}

=== Method 2 ===

Install the current version of the spkg, and copy the new files into a new
folder. Then run

{{{
sage: C = sage.databases.cremona.LargeCremonaDatabase('cremona',False)
sage: C._init_from_ftpdata('path/to/said/folder',0)
}}}

This method is much faster, but won't include any potential fixes old entries.